US Senator Scott Brown today defended his aggressive debate performance and amplified one of his attacks from Thursday night’s showdown with Elizabeth Warren, accusing her of hypocrisy for representing an insurance company in an asbestos lawsuit.

Kicking off the morning after the debate, Brown, a Republican, held a press conference at his campaign headquarters in South Boston, hours before Warren, a Democrat, is to receive the endorsement of Boston Mayor Thomas M. Menino, a fellow Democrat, at a rally in Roslindale.

At his headquarters, Brown stood before a bank of television cameras and held up a bundle of papers that he said showed the $212,000 that Travelers Insurance paid Warren for her work over three years in the lawsuit.

Brown said Warren’s advocacy on behalf of the insurance giant flies in the face of her reputation for sticking up for “little guys” and working people.

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“Now, I don’t know anybody who’s hired by an insurance company that was actually working for the victims,” Brown said. “Huge insurance corporations don’t hire big-time attorneys from Harvard to fight against their interests for their opponents, which would be the victims.”

Brown was picking up on an attack that political observers said seemed to throw Warren off her footing in Thursday night’s debate. She struggled to explain her role in the lawsuit, and emphasized that the Boston Globe had written extensively about the case.

In the asbestos case, Warren did represent Travelers but, at the time, the company was seeking to unlock a $500 million settlement account for victims, a step many asbestos victims supported. After Warren left the case, however, Travelers won a separate court ruling that allowed the company to avoid paying out the settlement. That ruling is under appeal.

“Elizabeth Warren got involved to protect the settlement,” against a challenge from another insurance company, said David J. McMorris, a lawyer at Thornton & Naumes in Boston, who represented victims in the case.

McMorris and several officials from an asbestos workers’ union stood outside Brown’s headquarters after the senator’s press conference and defended Warren’s role in the lawsuit.

“It should be very, very clear the victims would have no chance to get paid by Travelers were it not for the work of Elizabeth Warren,” McMorris said. “She’s been with the victims then, and she’s with the victims now.”

McMorris has donated $467,435 To Democratic politicians, according to the Brown campaign, which sent out a press release about McMorris’s contributions this morning.

Scott Curry, regional organizer for the Insulators and Asbestos Workers Union, said he was outraged at Brown’s attacks. His union, which includes asbestos victims in the Travelers’ case, has endorsed Warren.

Curry said members of his own family have died from asbestos poisoning and “I don’t need a guy like Scott Brown talking about this or that, when he doesn’t really know where he’s coming from when it comes to this,” Curry said. “He’s stepping out of his league, out of bounds.”

At his press conference, Brown, who has emphasized his likeable, everyman image, also pushed back against pundits who said he was too zealous in his attacks on Warren during their first debate.

“Listen, I’m very passionate about my job, and about representing the people of Massachusetts,” Brown said. “And when she’s distorting and misleading people about my record and my votes, I’m going to obviously be passionate about it. I don’t think there’s any aggressiveness. I think we’re both very firm in our positions and I think the voters were treated to a great debate.”

Brown downplayed the significance of the Menino endorsement, pointing out that he has the backing of former Boston mayor Raymond L. Flynn, as well as former Democratic mayors of Lowell, Worcester, and Springfield. He also made a point of praising Menino, who has the power to turn out votes for Warren in vote-rich Boston neighborhoods.

“I consider Mayor Menino a friend, somebody I have a lot of respect for,” Brown said. “I’m going to continue to work with him and for the city of Boston… I’m going to continue to try to earn the respect of the mayor and let the voters know that regardless of that endorsement, I’m going to be working for the city of Boston.”

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